Shaped charges



June 24, 1958 J. H. CHURCH ETAL SHAPED CHARGES Filed May l2, 1950 Jnseph H. Church. lrggnry f T. Keelisenich mM/MM liaise SHAPED CHARGES .loseph H. Church, Austin, Minn., and Gregory J. Kessenich, Madison, Wis., assgnors to the UnitedV States of America as represented by the Secretary of the Army The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment to us of any royalty, thereon or therefor.

This invention relates to shaped charges especially adapted to use for special purposes, such as the production of a series of closely spaced holes in a target.

The charge of this invention is especially adapted for use with the apparatus shown in copending application Serial Number 159,914, filed May 4, 1950, which matured to U. S. Patent No. 2,682,834 on July 6, 1954.

Various objects of the invention will be apparent from the following descriptionwhen considered with the appended drawings, in which:

Fig. l is a plan view of a preferred form of charge embodying the features of this invention,

Fig. 2 is a sectional view taken upon the line 2 2 of Fig. l,

Fig. 3 is a sectional view similar to' Fig. 2 showing a modified form of charge,

Fig. 4 is a sectional view similar to Figs. 2 and 3 showing another modified form of charge,

Fig. 5 is a longitudinal sectional view of a fuse especially adapted to use for detonating charges of-the type shown herein, and

Fig. 6 is a sectional view taken upon the line 6-6 of Fig. 5.

The charge 10 as shown in Figs. 1 and 2 comprises an explosive body 11 formed of any appropriate detonable explosive which is symmetrically arranged about a central axis 12 and bounded by opposed parallel surfaces 13, 14. The latter opposed surfaces are joined by an intervening edge surface 15 to define a peripheral bounding edge surface for the explosive body. At uniformly spaced intervals circumferentially of the body the edge surface 15 is indented to provide a plurality of radial symmetric reentrant primary cavities 16, which as shown, open radially outward of the charge in diverging relation. Although the cavities 16 are shown to be of modied or general V-shape in horizontal cross-section it is to be appreciated that they may be of any suitable radial symmetric cross section.

The peripheral edge surface 15 may throughout each indented portion thereof be further recessed in symmetric relation to a median plane 17 of the explosive body 11 to form a secondary cavity 18 within each of the primary cavities 16. As in the case of the primary cavities the secondary cavities 18 may likewise be of any appropriate symmetric form.

Safes Parmi of anyY metallicor'unon-metallic materialU suitable f.for` .the jf purpose.

The charge Y' to the charge shown in Figs. 1 and 2 exeptthat the opposed parallel surfaces 24, 25 are conical in formwhereby the directed force eiectaccomplished by each `of the f cavities will be at an angle other than normal to the axis 12 of the charge which is advantageous'inthe charge when used in some environments.

In Fig. 4V weV have shown a moditedforrn of charge which is similar to the charge shown in Figs..1 and 2.

In this case the primary cavities 26 are of different symmetric Yform than thepprimary cavities shown in Figs. l and 2 and the explosive body has been cavitatedso as to permit portions 27thereof to extend to the 'periphery of the 4charge over. and under the Vcavities as shown.` The opposed charge encasing plates in this case are shown as circular plates 28, 29 which etxend to the periphery of-the charge andV may carry inwardly projecting Hang-es 3b which in Yturn support strips 31 of any suitable material to retain Vthe vliners 32 and explosive portions 27 in place;

We mayV also use circular plates in lieu of the plates 20 and 21 in any case where it is desirable to cover opposed sides of the cavities 16 in the planes of the plates 20, 21.

The chargesiwe have shown may be detonated by primacord extending through the bores 19 formed in the charges. In this system, using a primacord detonator,

- detonation of the explosive body 11 will be progressively propagated along bore 19 from apoint adjacent either surface 13 or 14 through the entire charge. If the detonation velocity of the primacord is greater than that of the explosive body, the rate of initiation along bore'19 will be equal to the detonation velocity of the primacord, and the desirable instantaneous initiation of the walls of bore 19 can be approached. This system because of its simplicity and comparative good results can ordinarily be tolerated, however,V where greater efciency of the charge is desired we prefer to use a detonator or initiator of the type shown in Figs. 5 and 6.

As indicated the detonator 33 may be comprised of a tubular element 34 made of any appropriate metallic or non-metallic material intended to function primarily as a housing element for the detonator. Within the element 34 there is inserted a tubular element 35 of detonable explosive exteriorly shaped to provide a plurality of radial symmetric outward opening cavities 36 uniformly spaced circumferentially of the element and extending in linear parallel axial relation thereof. A resistance element 37 is disposed through the bore of the tubularexplosive element 35 in central relation thereto and is connected integrally or otherwise suitably al`xed at either end to leads 38, 39 adapted to be circuited with a source of power not shown. Fuse powderfill adapted to be ignited by'resistance element37 and in turn adapted to detonate the tubular explosive element 35 is packed within element 35 about the resistance element in any conven- The explosive body 11 is formed with an axial bore 19 ient manner. The ends of the tubular casing element 34 may be plugged with plugs 41 of sulphur or similar material to prevent moisture from gaining access to the .interior of the detonator'assembly. Depending upon the y character of the explosive used to formkthe body 11 a booster mayor may not be employed in conjunction with the detonator as will be weil understood in the art.

We claim: Y 1. A shaped explosive charge comprising ak pairk of identical star-shaped sheets of material havingV uniformly'V angularly spaced arms, means connecting said sheets in parallel axially spaced relation, said means comprising a strip of material having parallel edges securedV to and extending alongY the respective contiguous edges of said star-shaped sheets to form therewith a completely closed shown Yin Fig. 3 is similar in all respects-Y wardlyprojecting continuous channel generally V-shaped in radial cross section and between and parallel with its edges, and an explosive charge completely illingV said closed container.

2. YA Shaped explosive charge comprising Va pair-of identical star-'shaped sheets of materialV having uniformly angularlyl spaced arms, means connecting said sheets in parallel axially-spaced relation, said means comprising a strip of material having parallel edges secured to and extending along the respective contiguous edges of said star-shaped sheets to form therewith a completely closed star-shaped container, said strip of material having an inwardly projecting continuous channel generally V-shaped in radial cross section and between and parallel with its edges,'and an explosive charge completely lling said closed container, the arms of said star-shaped sheets being truncated to lie in the surface of a common cylinder coaxial with the central axis of said sheets.

3. A shaped explosive charge comprising a pair of 20 identical star-shaped sheets of material having uniformly angularly spaced arms, means connecting said sheets in parallel axially spaced relation, said means comprising a strip of material having parallel edgessecured to and extendingalong the respective contiguous edges of said star-shaped sheets to form therewith a completely closed star-shaped container,` said strip of material having an inwardlyprojecting continuous channel generally V-shaped in radial cross section and between and parallel with its edges, and an explosive charge completelylling said closed container, said sheets being in the form of right cones of equal obtuse apex angles with coincident axes.

References Cited in the le of this patent UNITED STATES PATENTS 2,494,256 Muskat et al. Ian. 10, 1950 2,506,836 Kaltenberger May 9, 1950 2,513,233 Byers June 27, 1950 2,587,243 Sweetman Feb. 26, 1952 FOREIGN PATENTS Y 369,237 Italy Mar. 15, 1939 618,617 Great Britain Feb. 24, 1949 OTHER REFERENCES Neumann Zeitschrift fur Das Gesamte Schiess and Sprengstoievesen, May 15, 19,14, pp. 184 and 186 (complete article pages 183-187). 

